Developing apparatus and developing method

ABSTRACT

A developer nozzle is moved from a periphery of a wafer toward the central portion while an exposed substrate held at a spin chuck is being rotated about a vertical axis and while a developing solution is being discharged from the developer nozzle, and this way the developing solution is supplied to the surface of the wafer, the developer nozzle having a slit-like ejection port whose longitudinal direction is oriented to the direction perpendicular to the radial direction of the wafer. The movement speed of the nozzle is higher than a case where a nozzle with a small-diameter circular nozzle is used, and this enables a development time to be reduced. Further, the thickness of a developing solution on a substrate can be reduced, so that the developing solution can be saved.

CROSS REFERENCE

This application is a division of and is based upon and claims thebenefit of priority under 35 U.S.C. §120 for U.S. Ser. No. 10/584,264,filed Jun. 26, 2006, the entire contents of which are incorporatedherein by reference, which is a National Stage of PCT/JP04/19417, filedDec. 24, 2004, and claims the benefit of priority under 35 U.S.C. §119from Japanese Patent Application No. 2003-435897, filed Dec. 26, 2003and Japanese Application No. 2004-233617, filed Aug. 10, 2004.

TECHNICAL FIELD

The present invention relates to a developing apparatus and method fordeveloping an exposed resist on a substrate surface.

Background Art

A semiconductor manufacturing process includes a photoresist process inwhich a resist is coated onto the surface of a semiconductor wafer(hereinafter referred to simply as a wafer), exposed in a predeterminedpattern, and then developed to form a resist pattern. Such a process isgenerally performed by a system in which a coating-and-developingapparatus for coating-and-developing a resist is connected to anexposure apparatus.

The operation of the developing apparatus disclosed in JP7-263302A willbe described with reference to FIG. 17. First, a wafer W is held in ahorizontal attitude on a spin chuck 1, and a developer nozzle 11 ispositioned such that its small diameter ejection port is locatedslightly higher than the surface of the wafer W. Then, the developernozzle 11 is moved in a radial direction relative to the rotational axisof the wafer W while ejecting a developing solution through thedeveloper nozzle 11 and while rotating the wafer W around a verticalaxis. This causes the developing solution to be accumulated on thesurface of the wafer W in a spiral manner, as shown in FIG. 17( a).Then, the wafer W with the developing solution 12 accumulated on itssurface is left for a predetermined developing time (e.g., 60 seconds)to cause “stationary development” of the resist, as shown in FIG. 17(b). After that, a rinse liquid 14 (e.g., deionized water) is supplied tothe center portion of the wafer W through a rinse liquid nozzle 13, asshown in FIG. 17( c). As a result, the portions of the resist insolublein the developing solution remain, forming a predetermined resistpattern.

In the developing apparatus disclosed in JP2001-284206A, the developernozzle 11 and the rinse nozzle 13 are mounted on the same nozzle arm(not shown) such that they are adjacent each other in the travelingdirection of these nozzles, as shown in FIG. 18. When developing theresist on the wafer W, the developer nozzle 11 and the rinse nozzle 13are moved from the periphery of the wafer W toward the center portionwhile ejecting a developing solution and a rinse liquid simultaneouslythrough these nozzles and while rotating the wafer W on the spin chuck 1around a vertical axis. Thus, the resist on the wafer W is developedwhile removing the developing solution right after it is supplied to thesurface of the wafer W by using the rinse liquid.

However, the above developing method suffers from the following problem.When the resist on the wafer W is developed by using a puddle method(i.e., stationary development) disclosed in JP7-263302A that developsthe resist with a developing solution accumulated on the wafer Wsurface, a pullback phenomenon occurs if the amount of developingsolution accumulated on the wafer W is too small, since the resist isgenerally hydrophobic. In this pullback phenomenon, small amounts ofliquid, or developing solution, collected in different places on thewafer W pull each other due to surface tension, which may preventcontact between some portions of the resist and developing solution andhence prevent development of these portions. To overcome this problem, alarge amount of developing solution must be supplied to the surface ofthe wafer W. However, this consumes a large amount of developingsolution, increasing the manufacturing cost of the semiconductor device.

A puddle-less method (without performing stationary development)disclosed in JP2001-284206A is one of solutions for the foregoingproblem. However, if the size of the ejection port of the developernozzle is reduced to reduce the amount of developing solution consumed,it takes a long time to apply a developing solution to the entiresurface of the wafer W, resulting in increase of the developing time.Furthermore, different portions of the wafer W may be in contact withthe developing solution for different amounts of time, resulting indegradation of in-plane uniformity of the developing process.

Further, the following problem arises when the developing solution isremoved immediately after its application by supplying deionized waterthrough the rinse nozzle disposed adjacent the developer nozzle asdisclosed in JP2001-284206A. It is not possible to ensure a developingtime long enough to develop a resist having a low dissolution rate inthe developing solution. As a result, there occurs under-development,which means that the sides of the bottom portion of a groove formed inthe resist film are not sufficiently dissolved and remain. This resultsin variations in line width of the resist pattern.

DISCLOSURE OF THE INVENTION

The present invention has been made in view of the above problems. Itis, therefore, an object of the present invention to provide anapparatus and method capable of developing an exposed resist on asubstrate surface in a short time with a reduced amount of developingsolution.

According a first aspect of the present invention, there is provided adeveloping apparatus including: a substrate holding unit that holds asubstrate in a horizontal attitude, the substrate having an exposedresist thereon; a rotational drive mechanism that rotates the substrateholding unit, holding the substrate, around a vertical axis; a developernozzle that ejects a developing solution toward the substrate, thedeveloper nozzle having an ejection port having a shape of an elongatedslit; and a moving mechanism that moves the developer nozzle in asubstantially radial direction of the substrate, the moving mechanismincluding a nozzle support unit to support the developer nozzle; whereinthe nozzle support unit of the moving mechanism is configured tosupports the developer nozzle such that a longitudinal direction of theejection port is oriented toward a center portion of the substrate whenthe ejection port is located above the substrate; and wherein saiddeveloping apparatus is configured so that the developer nozzle is movedfrom a peripheral portion of the substrate toward the center portion ofthe substrate while ejecting the developing solution in a form of astrip through the ejection port and while rotating the substrate aroundthe vertical axis, thereby to supply the developing solution to asurface of the substrate in a spiral form.

Preferably, the ejection port has a width in a range of 0.1 mm to 1 mmand a length in a range of 8 mm to 15 mm. The developing apparatus mayfurther includes a temperature regulating unit for controllingtemperature of the developing solution to be supplied from the developernozzle according to a type of the resist on the substrate or a specificgeometrical characteristic of a pattern of the resist. In this case,preferably, there are provided plural number of said developer nozzles,and each of the developer nozzles is provided with a temperatureregulating unit to control the temperature of a developing solution; andmeans for selecting a particular one of the plurality of developernozzles, wherein the temperature of the selected developer nozzle hasbeen adjusted according to a type of the resist to be developed on thesubstrate or a specific geometrical characteristic of a pattern of theresist. Further in this case, while said one developer nozzle isselected, the temperature of a developing solution for another developernozzle is adjusted. The temperature regulation may be carried out by acontrol unit that stores data showing relationship between types ofresists on the substrate to be developed or specific geometricalcharacteristics of patterns of the resists and developing solutiontemperatures suitable therefor, and that controls, based on the data,the temperature regulating unit to adjust the temperature of adeveloping solution to a value suitable for a resist to be developed.

Each or the developer nozzles may be provided with, in addition to thetemperature regulating unit, a concentration control unit forcontrolling a concentration of the developing solution. In this case,the temperature and the concentration of the developing solution for aselected developer nozzle may be adjusted according to the type of theresist or the specific geometrical characteristic of the pattern of theresist. Preferably, while one developer nozzle is selected, thetemperature and the concentration of a developing solution for anotherdeveloper nozzle are adjusted. The control of the temperature and theconcentration may be performed by a control unit that stores datashowing relationship between types of resists or specific geometricalcharacteristics of patterns of the resists and developing solutiontemperatures suitable therefor and developing solution concentrationssuitable therefor, and that controls, based on the data, the temperatureregulating unit and the concentration control unit to adjust thetemperature and the concentration of a developing solution to valuessuitable for a resist to be developed.

Preferably, the developing apparatus is further provided with a surfacetreatment liquid nozzle that supplies a surface treatment liquid to thesurface to enhance wettability of the surface before the developingsolution is supplied to the surface of the substrate. Alternatively, thedeveloping apparatus is further provided with a rinse liquid nozzle thatsupplies a rinse liquid to the surface of the substrate after thedeveloping solution is delivered to the surface; and an surfactantsupply nozzle that supplies a surfactant to the surface of the substrateafter the rinse liquid is supplied to the surface through the rinseliquid nozzle.

Preferably, the movement of the developer nozzle from the outer portionof the substrate toward the center portion of the substrate is stoppedwhen an end, on a side of the center portion of the substrate, of theejection port of the developer nozzle has reached a positioncorresponding to the rotational axis of the substrate.

According to a second aspect of the present invention, there is provideda developing method including the steps of: holding a substrate in ahorizontal attitude on a substrate holding unit, the substrate having anexposed resist thereon; moving a developer nozzle, ejecting a developingsolution in a form of a strip having a width oriented toward a centralportion of the substrate, from a periphery of the substrate toward acenter portion of the substrate, while rotating the substrate about avertical axis, thereby spirally supplying the developing solution onto asurface of the substrate while allowing the developing solution to flowradially outwardly; and stopping supplying the developing solutionthrough the developer nozzle and supplying a rinse liquid to the surfaceof the substrate through a rinse liquid nozzle. The supply of the rinseliquid may be initiated at the same time as the stoppage of supply ofthe developing solution, or it may be initiated slightly (e.g., 2seconds or less) before or after the stoppage of supply of thedeveloping solution.

Preferably, the ejection port of the developer nozzle has a width in arange of 0.1 mm to 1 mm and a length in a range of 8 mm to 15 mm.

Preferably, the temperature of the developing solution is controlledaccording to a type of the resist, to be developed, on the substrate ora specific geometrical characteristic of a pattern of the resist.

Preferably, the developing method further includes a step of selectingone of a plurality of developer nozzles, which have been set to ejectdeveloping solutions at different temperatures, based on a type of theresist to be developed on the substrate or a specific geometricalcharacteristic of a pattern of the resist. Preferably, the developingmethod further includes a step of, while one developer nozzle isselected, adjusting the temperature of a developing solution for anotherdeveloper nozzle.

Preferably, the temperature and concentration of the developing solutionare controlled according to a type of the resist, to be developed, onthe substrate or a specific geometrical characteristic of a pattern ofthe resist.

Preferably, the rinse liquid nozzle is moved to a position near thedeveloper nozzle before the developer nozzle stops ejecting thedeveloping solution.

The developing solution supplying step may include a step of moving thedeveloper nozzle from the periphery of the substrate toward the centerportion of the substrate a plurality of times while ejecting adeveloping solution through the developer nozzle.

The developing solution supplying step includes a step of supplying thedeveloping solution to the center portion for a predetermined period oftime, after moving the developing solution nozzle from the periphery ofthe substrate toward the center portion of the substrate.

The developing method may further include a step of supplying a surfacetreatment liquid to the surface of the substrate to enhance wettabilityof the surface of the substrate, before supplying the developingsolution. Alternatively, the developing method may further include thesteps of: supplying a rinse liquid to the surface of the substrate aftersupplying the developing solution; and supplying a surfactant to thesurface of the substrate, after supplying the rinse liquid.

In one preferred embodiment, the movement of the developer nozzle fromthe outer portion of the substrate toward the center portion of thesubstrate is stopped when an end, on a side of the center portion of thesubstrate, of the ejection port of the developer nozzle has reached aposition corresponding to the rotational axis of the substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a vertical cross-sectional view of a developing apparatus inone embodiment of the present invention.

FIG. 2 is a plan view of the developing apparatus in one embodiment ofthe present invention.

FIG. 3 is a perspective view of a developer nozzle of the developingapparatus.

FIG. 4 is a diagram illustrating a developer supply means of thedeveloping apparatus.

FIG. 5 is a diagram showing process steps of developing a wafer by usingthe developing apparatus.

FIG. 6 is a diagram illustrating the way of supplying a developingsolution to the surface of a wafer.

FIG. 7 is a diagram illustrating the way of supplying the developingsolution to the surface of the wafer.

FIG. 8 is a diagram illustrating the stop position of a developernozzle.

FIG. 9 shows graphs showing relationships between a line width of apattern and a developing time or a developing solution temperature.

FIG. 10 is a diagram illustrating ejection ports for a developer nozzlein other embodiments.

FIG. 11 is a diagram showing process steps of developing a wafer byusing the developing apparatus in another embodiment.

FIG. 12 is a diagram showing process steps of developing a wafer byusing the developing apparatus in still another embodiment.

FIG. 13 is a diagram illustrating a developer nozzle in anotherembodiment.

FIG. 14 is a diagram illustrating a developer nozzle in still anotherembodiment.

FIG. 15 is a plan view of a coating-and-developing apparatus, in oneembodiment, incorporating the developing apparatus.

FIG. 16 is a perspective view of the coating-and-developing apparatusincorporating the developing apparatus.

FIG. 17 is a diagram illustrating a conventional developing apparatus.

FIG. 18 is a diagram illustrating another conventional developingapparatus.

DESCRIPTION OF PREFERRED EMBODIMENTS

A developing apparatus in one embodiment of the present invention willbe described with reference to FIGS. 1 and 2. Reference numeral 2denotes a spin chuck (i.e., a substrate holding unit) for holding asubstrate (e.g., a wafer W) in a horizontal attitude by holding thecenter portion of the back side of the substrate by suction. The spinchuck 2 is connected to a drive mechanism 22 through a rotational shaft21 and can be rotated, raised and lowered together with the wafer W heldthereon, by the drive mechanism 22. In the illustrated embodiment, thewafer W is set on the spin chuck 2 such that the center of the wafer Wis located on the rotational axis line of the spin chuck 2. However, inthe present invention, the center of the wafer W need not necessarily bepositioned on the rotational axis. The center of the wafer W may belocated in a circular region of a radius in a range of 1 to 15 mmcentered about the rotational axis.

A cup set 3 is provided so as to surround the wafer W held on the spinchuck 2. The cup set 3 comprises an inner cup 32 and an outer cup 31each having an opened top end. The outer cup 31 has an upper portionthereof having a shape of a rectangular tube and a lower portion thereofhaving a cylindrical shape. The inner cup 32 has a shape of a cylinderhaving an upper portion thereof tapered inwardly. The outer cup 31 israised and lowered by an elevating mechanism 33 connected to the lowerend of the outer cup 31. The inner cup 32 is raised when a shoulderformed on the inner circumferential surface of the lower end of theouter cup 31 pushes the inner cup 32.

A circular plate 34 is provided below the spin chuck 2. A liquidreceiver 35 having a shape of a substantially rectangular groove incross section is provided outside the circular plate 34 to extend alongthe entire circumference of the circular plate 34. A drain port 36 isformed in the bottom of the liquid receiver 35. The developing solutionand the rinse liquid that have dropped or been spun off from the wafer Ware trapped within the liquid receiver 35, and are discharged from thedeveloping apparatus through the drain port 36. A ring member 37 havinga substantially triangular cross-sectional shape is provided outside thecircular plate 34. Three lifting pins (not shown) penetrate through thecircular plate 34. These lifting pins and a not shown substrate conveyercooperate to allow the wafer W to be transferred to and from the spinchuck 2.

There will now be described a developer supply means for delivering adeveloping solution (i.e., developer) to the surface of the wafer W. Thedeveloper supply means includes a first developer nozzle 4A and a seconddeveloper nozzle 4B that are capable of vertical movement and horizontalmovement. The developer nozzles 4A and 4B have the same configuration.Each component of the developer nozzle 4B corresponding to that of thedeveloper nozzle 4A is denoted by the same reference number while thesuffix “A” attached to the reference numeral of the latter is replacedwith the suffix “B” attached to the reference numeral of the former.

As shown in FIG. 3, the developer nozzle 4A may be formed in a wedgeshape whose width is reduced as approaching the lower end thereof. Anejection port 41A having a shape of an elongated slit is formed in thelower end surface of the nozzle to eject a developing solution in a formof a strip. The open end of the ejection port 41A has a rectangularshape and has a length L1 in a range of 8 to 15 mm and a width L2 in arange of 0.1 to 1 mm, preferably 0.1 to 0.5 mm. When ejecting adeveloping solution, the ejection port 41A is positioned such that itslength L1 direction (longitudinal direction) thereof aligns with a linepassing through the peripheral edge of the wafer W and the centerportion of the wafer W. It should be noted that “the line passingthrough the peripheral and the center portion of the wafer W need notnecessarily be a radial line passing through the center of the wafer W.That is, it is only necessary that the length L1 direction of theejection port 41A be substantially aligned with a radial direction ofthe wafer W. The open end of the ejection port need not necessarily havean exact rectangular shape in cross section. Thus, corners of therectangle may be rounded; a short side of the rectangle may be oblique;and/or the open end of the ejection port may have a serpentine profile.

As shown in FIG. 4, the ejection port 41A is communicated with a liquidbuffer portion (or liquid buffer chamber) 42A formed within thedeveloper nozzle 4A. The liquid buffer portion 42A is connected to oneend of a developer tube 43A (supply passage), and the other end of thedeveloper tube 43A is connected to a developer supply source 44A. A maintemperature regulating unit 45A for adjusting the temperature of adeveloping solution and a liquid feeding means (not shown) are providedin the developer tube 43A. For example, the main temperature regulatingunit 45A may be a heat exchanger, and the liquid feeding means may be abellows pump whose discharge flow rate can be controlled by changing thedischarge stroke. A portion of the developer tube 43A runs inside of atemperature-control water tube 46A that constitutes atemperature-control water flow passage, thus forming a double tubestructure 47A composed of the developer tube 43A and thetemperature-control water tube 46A. In the example shown, atemperature-control water buffer portion (temperature-control waterbuffer chamber) 48A is provided on the liquid buffer portion 42A, andthe temperature-control water tube 46A is connected to the upper end ofthe temperature-control water buffer portion 48A. Thus, the double tubestructure 47A runs from the upper end of the temperature-control waterbuffer portion 48A to a predetermined position along the upstreamportion of the developer tube 43A. The double tube structure 47Aconstitutes an auxiliary temperature regulating unit. Heat is exchangedbetween the developing solution and the temperature-control waterthrough the tube wall separating the developer passage from thetemperature-control water passage (i.e., the tube wall of the developertube 43A), in order to adjust the temperature of the developing solutionto a predetermined value. The temperature-control water tube 46A leavesthe developer tube 43A at one end of the double tube structure 47A andextends to the temperature-control water buffer portion 48A. Therefore,the temperature-control water tube 46A forms a circulation passage, inwhich a temperature regulating unit 49A (for example, a heat exchanger)is provided. The main temperature regulating unit 45A and the doubletube structure 47A (functioning as an auxiliary temperature regulatingunit) are capable of adjust the temperature of the developing solutionto a predetermined value in a range of 5° C. to 60° C., for example.Note that one of the main temperature regulating unit 45A and theauxiliary temperature regulating unit may be omitted.

Referring back to FIG. 2, the developer nozzles 4A (4B) is supported onone end of a nozzle arm 5A (5B). The other ends of the nozzle arm 5A(5B) is connected to moving base 51A (51B) including an elevatingmechanism (not shown). The moving base 51A (51B) can be moved along theguide member 52A (52B) extending on the bottom surface of the enclosureof this developing apparatus (developing unit) in the X-direction.Further, in the figure, reference numeral 53 denotes a waiting area forthe developer nozzle 4A (4B). The tip portion of each nozzle is cleaned,etc. in the nozzle waiting area 53.

The developing apparatus further includes a rinse liquid nozzle 6 whichis capable of horizontal movement and vertical movement. The rinseliquid nozzle 6 has a fine ejection port 60 for ejecting a rinse liquidsuch as deionized water against the wafer W when it faces the surface ofthe wafer W. A rinse liquid supply source 62 is connected to the rinseliquid nozzle 6 through a rinse liquid tube 61 (i.e., a supply passage)(see FIG. 1), which is provided therein with a liquid feeding means (notshown), for example, a bellow pump whose discharge flow rate can becontrolled by changing the discharge stroke. The rinse liquid nozzle 6is connected through a nozzle arm 63 to a moving base 64 including anelevating mechanism (not shown). The moving base 64 is moved along theguide member 52A, shared by the moving base 51A for the developer nozzle4A, such that the first developer nozzle 4A and the rinse liquid nozzle6 do not interfere with each other. In FIG. 2, reference numeral 65denotes a waiting area for the rinse liquid nozzle 6.

Referring to FIG. 2, reference numeral 7 denotes a control unit forcontrolling the entire operation of the developing apparatus.Specifically, the control unit 7 has functions to: control theoperations of the drive mechanism 22, the lifting/lowering unit 33, andthe moving bases 51A, 51B and 64; and control the temperature controloperations of the main temperature regulating unit 45A (45B), the doubletube structure 47A (47B) (i.e., the auxiliary temperature regulatingunit), and the temperature regulating unit 49A (49B) so as to adjust thetemperature of the developing solution supplied to the surface of thewafer W to the predetermined value. A storage unit (e.g., a memory)provided in the control unit 7 stores data showing relationship betweenvarious types of resists and developing solution temperatures (which isin a range of 5° C. to 60° C.) suitable for developing respective typesof resists. The control unit 7 refers to this data to determine thedeveloping solution temperature for the type of resist coated on thewafer W to be developed. In other words, the control unit 7 determinesthe temperature of the developing solution based on the dissolutioncharacteristics of each type of resist in the developing solution andcontrols the operation of each temperature regulating unit accordingly.The control unit 7 may be adapted such that the operator enters thedeveloping solution temperature by using an input means of the controlunit 7, instead of automatically determining it based on the data storedin the memory as described above.

The following are exemplary developing solution temperatures. When theresist to be developed is for a KrF light source and has a lowdissolution rate in the developing solution, the developing solutiontemperature may be set in the range of 40° C. to 60° C. When the resistis for an ArF light source (studied for application in recent years) andhas a high dissolution rate in the developing solution, the developingsolution temperature may be set in the range of 20° C. to 40° C. In thecase of a resist for an i-ray source or a g-ray source, which readilydissolves at low temperatures, the developing solution temperature maybe set in the range of 10° C. to 20° C. The developing solutiontemperature for each resist is determined based on the temperature atunder which dissolution of the resist is promoted, not on the type ofthe light source used to expose the resist.

Then, process steps for developing the wafer W by using the developingapparatus will be described. The developing apparatus is initially setsuch that: the outer cup 31 and the inner cup 32 are located at theirlowered positions; and the developer nozzles 4A and 4B and the rinsenozzle 6 are positioned above the nozzle waiting areas 53 and 65,respectively. First, a wafer W having an exposed resist thereon istransferred to the developing apparatus by a substrate conveyer (notshown). This substrate conveyer and lifting pins (not shown) cooperatesto transfer the wafer W to the spin chuck 2. Before the wafer W istransferred to the spin chuck 2, the control unit 7 determines thedeveloping solution temperature based on the type of resist coated onthe wafer W and based on information stored in the memory (describedabove). Furthermore, the control unit 7 selects a nozzle used fordevelopment of this wafer W from the two developer nozzles 4A and 4B (inthis example, selects the first developer nozzle 4A), and causes themain temperature regulating unit 45A and the auxiliary temperatureregulating unit to adjust the temperature of the developing solution tobe ejected through the selected developer nozzle 4A such that itcoincides with the determined developing solution temperature. As aresult, the temperature-controlled developing solution stored in thedeveloping solution buffer portion 42A and in the developer tube 43Aupstream of the developing solution buffer portion 42A is ready to beejected through the developer nozzle 4A.

Then, the outer cup 31 and the inner cup 32 are moved to their raisedpositions, and the selected developer nozzle 4A is moved to adeveloper-ejection start position which is slightly outside theperipheral edge of the wafer W on one side of the wafer W and isslightly higher than the surface of the wafer W, while the rinse liquidnozzle 6 is moved so as to position the ejection port 60 at a locationwhich is slightly outside the peripheral edge of the wafer W on theopposite side of the wafer W and is slightly higher than the surface ofthe wafer W, as shown in FIG. 5( a). In the illustrated embodiment, theejection port 41A of the developer nozzle 4A is located 1 to 20 mmhigher than the surface of the wafer W. Note that, although the otherdeveloper nozzle 4B is staying above the nozzle waiting area 53 atpresent, preparation for processing of the next wafer W is carried outwhile this wafer W is being processed, as described later.

Then, the developer nozzle 4A moves from outside the wafer W toward thecenter portion along a line passing through the rotational center of thewafer W while ejecting a developing solution in a form of a strip fromthe ejection port 41A and while rotating the wafer W around a verticalaxis at a rotational speed of 500 rpm or higher, for example, 1000rpm-1200 rpm. In the case of an eight inch wafer W, for example, themoving speed of the developer nozzle 4A is set such that it takes 1-2seconds for the nozzle to move from the peripheral edge of the wafer Wto a position above the center portion of wafer W, for example, thecenter of the wafer W. It should be noted that the rotational speed ofthe wafer W and the moving speed of the nozzle are preferably set suchthat a strip of developing solution D are coated on the wafer W withoutany gap being defined between radially adjacent portions of the strip.These speeds may be determined through calculation based on the width ofthe strip of developing solution D, i.e., the length L1 of the ejectionport 41A, through experiments conducted beforehand. The developer nozzle4A may be moved such that the ejection port 41A is moved along a lineslightly translated from a line passing through the rotational center ofthe wafer W; for example, the ejection port may be moved along a linepassing through a region defined between the above line (passing throughthe rotational center) and a parallel line spaced from it by a distanceof 1 mm. Note that the present inventors have found, throughexperiments, that it is not possible to ensure a desired in-planeuniformity of the line width of a pattern if it is developed at a waferrotational speed of less than 500 rpm.

According to the above coating method, as shown in FIG. 6, astrip-shaped developing solution D is spirally applied to the surface ofthe wafer W so that no gaps are formed between radially adjacentportions of the spiral strip, thus covering the entire surface of thewafer W with the developing solution D. Since the wafer W is rotated,the developing solution D spreads outward on the surface of the wafer Wdue to centrifugal force, thereby forming a thin liquid film on thesurface of the wafer W, as shown in FIG. 7. The portions of the resistsoluble in the developing solution D dissolve, while those portions ofthe resist insoluble in the developing solution D do not dissolve andremain, to form a resist pattern.

When the ejection port 41A has reached the center of the wafer W, inother words, when the vertical projection of the ejection port 41A ontothe wafer surface has reached the rotational center of the wafer, thedeveloper nozzle 4A stops moving and the ejection of the developingsolution through the ejection port 41A is stopped. Immediatelythereafter, the developer nozzle 4A is moved from above the wafer W toits retracted position. The nozzle is preferably stopped when the edgeof the ejection port 41A on the wafer W center side, that is, theleading edge of the ejection port 41A, has reached the rotational centerline of the wafer W or a point slightly (for example, 1 mm or less)beyond the center line. This procedure is advantageously reduces an areaof the wafer W in the center portion thereof to which a developingsolution is applied twice.

It is acceptable if there are minute gaps between raidially adjacentportions of the strip of the developing solution immediately after thedeveloping solution is coated onto the wafer W. These minute gapsdisappear when the developing solution spreads due to centrifugalforces. It is also acceptable if radially adjacent portions of the stripof the developing solution overlap each other immediately after thedeveloping solution is coated onto the wafer W. However, it ispreferable to minimize the size of the overlap in order to save thedeveloping solution.

At the same time that the developer nozzle 4A move toward the center ofthe wafer W, the rinse liquid nozzle 6 on the side of the wafer Wdiametrically opposite to the developer nozzle 4A is also moved towardthe center of the wafer W and then stopped at a position (waitingposition) slightly before a position above the center of the wafer W.

Immediately after the developer nozzle 4A stops the ejection of thedeveloping solution and is moved from above the wafer W to its retractedposition, the rinse liquid nozzle 6 staying at the waiting positionmoves to a position above the center of the wafer W and a rinse liquid Ris ejected through the rinse liquid nozzle 6 for a predetermined periodof time, as shown in FIG. 5( c). In this embodiment, as the developernozzle 4A and the rinse liquid nozzle 6 are quickly switched, thedeveloping time is substantially equal to the time required for movingthe developer nozzle 4A from outside the wafer W toward the center ofthe wafer W. Note that the rinse liquid R may be supplied any timebefore the developing solution dries. Therefore, in order to ensure adeveloping time long enough to match the dissolution rate of the resist,the rinse liquid may be supplied an appropriate time after the ejectionof the developing solution is stopped. The appropriate time variesdepending on the rotational speed of the wafer W and may be, forexample, 2 seconds or less at a wafer W rotational speed of 500 rpm orhigher. In this case, the developing time is the sum of the travelingtime (scan time) of the developer nozzle 4A and the period of time froma point of time when the developer nozzle 4A stops ejecting thedeveloping solution to a point of time when the rinse liquid nozzle 6begins to eject the rinse liquid R. Note that the ejection of the rinseliquid R need not necessarily be begun after stopping the ejection ofthe developing solution D. That is, ejection of the rinse liquid R maybe initiated just before stopping the ejection of the developingsolution D.

The rinse liquid R supplied to the surface of the wafer W spreadsoutward on the surface due to centrifugal force, washing away thedeveloping solution containing dissolved resist components from thesurface of the wafer W to clean the surface. Then, the ejection of therinse liquid R is stopped and the rinse liquid nozzle 6 is moved fromabove the wafer W to its retracted position. After that, the wafer W isrotated at a high speed (e.g., 2000 rpm) so that the spin-drying of thewafer W, by which liquids on the wafer surface are spun-off, isperformed, as shown in FIG. 5( d). Then, the outer cup 31 and the innercup 32 are lowered and the wafer W is transferred from the developingapparatus by the substrate conveyer (not shown). In this way, thedeveloping process is completed.

In a case where wafers W of a certain production lot (hereinafterreferred to as “first production lot”) are processed by using thedeveloper nozzle 4A and wafers W of a next production lot (hereinafterreferred to as “second production lot”) are subsequently processed aftercompletion of the processing of the first production lot, the developingsolution temperature for the wafers W of the second production lot isdetermined based on the type of resist on these wafers W, and the maintemperature regulating unit and the auxiliary temperature regulatingunit assigned to the developer nozzle 4B, which is standing-by, controlthe temperature of the developing solution for the developer nozzle 4Bbefore starting the process of the first wafer W of the secondproduction lot. After completion of the development of the wafers W ofthe first production lot, the wafers W of the second production lot aredeveloped by using the developer nozzle 4B according to the sameprocedure as described above. Note that, processing schedule dataindicating the number and the type of wafers W (or the type of resist onthe wafers W) to be processed is inputted beforehand into the memory ofthe control unit 7 through the input means. Based on this data, thecontrol unit 7 determines the temperature of the developing solution tobe prepared.

In the foregoing embodiment, the developing solution is supplied bymoving the developer nozzle 4A (4B) in a substantially radial directionof the wafer W, with the slit-shaped ejection port 41A (41B) ejectingthe developing solution, while the longitudinal direction of theejection port 41A (41B) is substantially aligned with the radialdirection. Thus, the following advantages are achieved. As a greaterlength L1 of the ejection port 41A (41B) results in a greater width ofthe strip of the developing solution supplied to the wafer W, allowingthe moving speed of the developer nozzle 4A (4B) to be increased. Thus,it is possible to reduce the time required for supplying the developingsolution and hence the time required for the developing process. As asmaller width L2 of the ejection port 41A (41B) results in a reducedthickness of the developing solution coated on the surface of the waferW, resulting in reducing the consumption of the developing solution. Thepresent inventors obtained the following experimental results. With thepuddle method (i.e., “stationary development”), 70 ml of developingsolution was required to develop a 12-inch wafer W. On the other hand,the foregoing method required only 16.7 ml of developing solution toachieve the same line width accuracy. However, in an actual developingprocess, the amount of developing solution is preferably set to 20 ml ormore in order to reliably wet all portions of the wafer W with thedeveloping solution D (that is, to provide a safety margin). Note that,if the length L1 of the ejection port 41A (41B) is too long, the supplyof developing solution to the center portion of the wafer W is notsmooth, resulting in generation of mist. If the length L1 is too short,the rotational speed of the wafer W must be increased, resulting in someof the developing solution being spun-off from the wafer W. If the widthL2 of the ejection port 41A (or 41B) is too large, a large amount ofdeveloping solution is consumed. If the width L2 is too small, it maynot be possible to eject a developing solution in a form of a strip.Therefore, the length L1 of the ejection port 41A (41B) is preferably ina range of 8 to 15 mm; and the width L2 is preferably in a range of 0.1to 1 mm, more preferably 0.1 to 0.5 mm.

According to the foregoing embodiment, as the wafer W is rotated when itis developed, in other words, when the developing solution is in contactwith the resist, it is possible to remove dissolved resist componentsfrom the surface of the resist in contact with the developing solution,especially from valley portions of the resist pattern. Dissolved resistcomponents left on the surface of the resist prevent further dissolutionof the resist. Dissolved resist components can be removed from thesurface of the wafer W by rotating the wafer W. Thus, the influence ofthe dissolved resist components is significantly reduced as comparedwith “stationary development”, and thus a resist pattern with sufficientline-width accuracy can be formed. Note that after the supply of thedeveloping solution, the wafer W need not necessarily be rotatedcontinuously. Even if the wafer W is intermittently rotated, dissolvedresist components can be removed as described above.

According to the foregoing embodiment, as the rinse liquid nozzle 6 ismoved to a location near the rinse liquid ejection position and standsby at the location until the ejection of the developing solution throughthe developer nozzle 4A (4B) is stopped, the rinse liquid can besupplied immediately after the completion of the supply of thedeveloping solution through the developer nozzle 4A (4B), therebyfacilitating development of a resist having a high development rate.Instead of arranging the developer nozzle 4A (4B) and the rinse liquidnozzle 6 separately, rinse liquid nozzles 6 may be mounted to the nozzlearms 5A and 5B for the developer nozzles 4A and 4B, respectively. Therinse liquid nozzle 6 may be inclined so as to supply the rinse liquidfrom the foregoing waiting position toward the center of the wafer W,eliminating the time required to move the rinse liquid nozzle 6 from theforegoing waiting position to the rinse liquid ejection position.

According to the foregoing embodiment, as a developing solution whosetemperature is adjusted to a value in correspondence to the type ofresist is supplied to the surface of the wafer W to develop the resist,it is possible to reduce the developing time of a resist having a lowdissolution rate. Therefore, the developing times of resists havingdifferent dissolution rates can be equalized or made close to eachother. This allows different types of resists to be developed by thesame developing apparatus under the same process conditions except fordeveloping solution temperature. In this case, if mechanisms included inthe developing apparatus cannot accommodate the process conditionsrequired by the resist having the highest dissolution rate, the processconditions may be set for a resist having a dissolution rate somewhatlower than the highest one. FIG. 9( a) shows the relationship betweenthe developing time and the line width (CD) of the pattern for twodeveloping solution temperatures, in a certain developing solution.Curve (1) shows the relationship at 23° C. (clean room temperature), andcurve (2) shows the relationship at 50° C. The developing solution has aproperty that its resist dissolution rate increases with increasing intemperature. More specifically, if the desired line width is 150 nm, thetime required to achieve the desired line width was 50-60 seconds at 23°C., and approximately 10 seconds at 50° C.

The developing time required to form an appropriate pattern variesdepending on not only the type of resist but also geometrical factorsspecifying the pattern. Therefore, the developing solution temperaturemay be changed according to the geometrical factors. The geometricalfactors of a pattern include its desired line width, pattern density,and pattern shape. The pattern shape may be specified, for example,based on the shape of the portion of the resist dissolved due to thedeveloping process (for example, a straight groove, a cylindrical hole,etc.), and on the area ratio of the grooves and holes in the pattern.Specifically, the developing solution temperature may be lowered fordense patterns and raised for rough patterns. Note that the developingsolution temperature may be changed according to both the type of resistand the geometrical factors of the pattern. FIGS. 9( b) and 9(c) aregraphs illustrating experimental results, wherein: FIG. 9( b) shows therelationship between the developing solution temperature and the linewidth (CD) when forming grooves; and FIG. 9( c) shows the relationshipbetween the developing solution temperature and the line width (CD) whenforming holes. The developing time was 10 seconds in both cases. Thesegraphs indicate that the pattern line width has greater temperaturedependence when forming grooves than when forming holes. Therefore, whengrooves and holes are formed at once, the developing solutiontemperature may be determined with placing priority on the developingconditions of the grooves.

According to the foregoing embodiment, the developing apparatus includestwo separate developer nozzles 4A and 4B adapted to control thetemperatures of the developing solution to be supplied therefrom atdifferent values independently. Therefore, when wafers W of a certainproduction lot are being processed by using one of the nozzles 4A and4B, the temperature of the developing solution for the other nozzle canbe adjusted to prepare for the processing of wafers W of the nextproduction lot. Thus, the first wafer W of the next production lot canbe processed immediately after completion of the development of the lastwafer W of the current production lot, which eliminates loss of timeincurred due to change in developing solution temperature, resulting inimproved throughput.

According to the embodiment described above, since a developing solutionis supplied from the developer nozzle 4A (4B) to the wafer W whilemoving the nozzle from the peripheral edge of the wafer W toward thecenter of the wafer W and while rotating the wafer W, any undevelopedregion (i.e., any region not yet contact with any developing solution)of the wafer W is first supplied with a fresh developing solutioncontaining no dissolved resist components. This reduces adverse effectsof the dissolved resist components, so that a pattern of high line-widthaccuracy may be achieved.

The concentration of the developing solution may be controlled, inaddition to its temperature. The concentration of the developingsolution can be changed by changing the flow rate ratio between thedeveloping solution and the deionized water mixed with it by using aflow rate control unit (not shown). Alternatively, a plurality ofdeveloper supply sources 48A (48B) may be provided so as to be able tosupply developing solutions of different concentrations. With thisarrangement, one of these developer supply sources 48 may be selectedaccording to the desired developing solution concentration by switchingvalves. The flow rate control unit and these valves constitute a portionof a developing solution concentration control unit.

In the present invention, the number of times of the nozzle scanningoperation, in which the developer nozzle 4A (4B) moves from theperipheral edge of the wafer W to the center portion of the wafer W isnot limited to one, may be plural number (e.g., 2-4 times or more). Thenumber of times of the scanning operation may be determined based on thetime required to develop the resist. Specifically, in a case where ittakes one second for the developer nozzle to move from the peripheraledge of the wafer W to the center portion of the wafer W, if therequired developing time is 10 seconds, the scanning operation isperformed ten times. In this case, the developing solution that issupplied first may be set to a different temperature and/or a differentconcentration than those of the developing solutions that are suppliednext (and subsequently). It is preferable to determine the change in thetemperature and the concentration of each developing solution throughexperiments. Specifically, in the second scanning operation, adeveloping solution having a lower concentration may be supplied, forexample. This limits the development reaction (or dissolution of theresist) and causes the dissolved resist components to diffuse, therebypreventing uneven development reaction due to these dissolved resistcomponents.

After the developer nozzle 4A (4B) is moved from the peripheral edge ofthe wafer W to the center portion of the wafer W, the developer nozzle4A (4B) may be held at a position above the center portion of the waferW for a predetermined period of time while continuing to supply thedeveloping solution. The period during which the nozzle is held may bedetermined based on the developing time required for the resist to bedeveloped. This step of holding the nozzle above the center portion ofthe wafer W while continuing to supply the developing solution throughthe nozzle may be combined with the foregoing step of performing aplurality of scaning operations.

Noted that it is not impossible to use the developing apparatus in theforegoing embodiment in such a manner that the developer nozzle 4A (4B)moves from the center portion of the wafer W to the peripheral edge ofthe wafer W, or moves from one end of the wafer W to the opposite end ofthe wafer W. However, when the developer nozzle is moved from the centerportion of the wafer W to the peripheral edge of the wafer, the supplieddeveloping solution may flow outward due to centrifugal force and thecenter portion of the wafer W may become dry, and thus such an operationrequires special attention.

The developing apparatus may include only one developer nozzle, insteadof the two developer nozzles 4A and 4B.

The above developing apparatus may be used while maintaining thedeveloping solution at a temperature of 23° C., which is equal to thetemperature of the clean room in which the developing apparatus isinstalled. Also in this case, uniform and favorable development of thewafer can be achieved due to the accurate temperature control functionof the temperature regulating units.

The developer nozzle 4A (4B) may have an ejection port with one of theshapes shown in FIG. 10, instead of the ejection port 41A (41B) whoseopen end has an elongated rectangular shape. FIG. 10 shows plan views ofejection ports as viewed from below. Specifically, the ejection portshown in FIG. 10( a) has an elliptical shape whose major axis is alignedin a radial direction of the wafer W; the ejection port shown in FIG.10( b) has a diamond shape whose longer diagonal is aligned in a radialdirection of the wafer W; the nozzle shown in FIG. 10( c) has aplurality of elongated rectangular ejection ports arrayed in a directionperpendicular to a radial direction of the wafer W; the nozzle shown inFIG. 10( d) has a plurality of round ejection ports arrayed in a radialdirection of the wafer W; and the nozzle shown in FIG. 10( e) has aplurality of round ejection ports formed in a zigzag arrangement.

Before supplying the developing solution to the surface of the wafer W,the surface of the wafer W may be supplied with a rinse liquid, such asdeionized water, as a surface treatment liquid for improving thewettability of the surface of the wafer W. This supply may be performed,for example, through the rinse liquid nozzle 6. Such a treatment isreferred to in this specification as pre-wetting. Pre-wetting may beperformed according to the following procedure.

After holding a wafer W in a horizontal attitude on the spin chuck 2,the rinse liquid nozzle 6 is moved from the peripheral edge of the waferW toward the center portion of the wafer W while ejecting a rinse liquidthrough the ejection port 60 and while rotating the wafer W around avertical axis, as shown in FIG. 11( a). Then, as shown in FIG. 11( b),the ejection of the rinse liquid is stopped and the rinse liquid nozzle6 is moved to a position slightly removed from the center of the wafer Wtoward the peripheral edge of the wafer W. At the same time, thedeveloper nozzle 4A (4B) is moved from the peripheral edge of the waferW toward the center portion of the wafer W while ejecting a developingsolution D through the ejection port 41A (41B), as previously described.

Supplying the developing solution after enhancing the wettability of thesurface of the wafer W prevents the developing solution from formingdroplets on the surface, allowing the developing solution to be reliablycoated on the entire surface of the wafer W without increasing itsamount, which is very advantageous in terms of reducing the developingsolution consumption. Instead of scanning the wafer surface with therinse liquid nozzle 6 ejecting a rinse liquid, the pre-wetting may beperformed by supplying a rinse liquid through the rinse nozzle 6positioned above the center portion of the wafer W while rotating thewafer W thereby spreading the rinse liquid over the entire surface ofthe wafer W by centrifugal force. A surface treatment liquid supplynozzle used exclusively for the pre-wetting may be provided separatelyfrom the rinse liquid nozzle 6.

An surfactant supply nozzle, which may be of the same shape as the rinseliquid nozzle 6, may be provided in the developing apparatus to supply asurfactant to the surface of the wafer W to which a developing solutionand a rinse liquid have been supplied; and the surfactant may besupplied to the surface of the wafer W before the spin-drying of thewafer W. Specifically, the surfactant may be supplied according to thefollowing procedure. First, a rinse liquid R is supplied by the rinseliquid nozzle 6 to the surface of the wafer W to which a developingsolution has been supplied, as shown in FIG. 12( a). Then, the supply ofthe rinse liquid R is stopped, and a surfactant supply nozzle 8 is movedfrom the peripheral edge of the wafer W toward the center portion of thewafer W while ejecting a surfactant through an ejection port 80, asshown in FIG. 12( b). Then, after stopping the supply of the surfactant,the surfactant supply nozzle 8 is moved from above the wafer W to itsretracted position, and the wafer W is rotated at a high speed tospin-dry it.

The surfactant thus supplied reduces the friction between the resistsurface and a liquid in contact with it. Thus, the liquid attached tothe surfaces of the pattern (specifically, the liquid attached to valleyportions of the pattern) is readily thrown from the wafer W withoutresistance in the spin-drying process. This prevents pattern collapsedue to the pulling force of the liquid thrown from the wafer W in thespin-drying process. Instead of scanning the wafer surface with thesurfactant supply nozzle 8 ejecting a surfactant, the surfactant may besupplied through the surfactant supply nozzle 8 positioned above thecenter portion of the wafer W while rotating the wafer W therebyspreading the surfactant over the entire surface of the wafer W bycentrifugal force. Further, instead of supplying a surfactant afterdelivering a rinse liquid R, a component acting as a surfactant may beadded to the rinse liquid R beforehand and may be supplied in the rinseprocess. In this case, the rinse liquid nozzle 6 also functions as thesurfactant supply nozzle 8.

Instead of arranging the developer nozzle 4A (4B) and the rinse liquidnozzle 6 (and the surfactant supply nozzle 8, if provided) to beseparately movable as described above, these nozzles may be mounted to acommon nozzle arm. For example, as shown in FIG. 13, the rinse liquidnozzle 6 and the surfactant supply nozzle 8 may be mounted on the tipportion of the nozzle arm 5A (5B) on which the developer nozzle 4A issupported. In this case, the rinse liquid nozzle 6 and the surfactantsupply nozzle 8 are inclined such that the axes of their ejection ports60 and 80 pass through the center portion of the surface of the wafer Wwhen the developer nozzle 4A (4B) is located at a position above thecenter portion of the wafer W. If a nozzle arm 5A (5B) is shared by thenozzles 4A (4B), 6, and 8, the configuration and the operation controlof the developing apparatus can advantageously be simplified. Thearrangement of the rinse liquid nozzle 6 and the surfactant supplynozzle 8 is not limited to that shown in FIG. 13. For example, as shownin FIG. 14, the rinse liquid nozzle 6 may be disposed behind thedeveloper nozzle 4A (4B) with respect to the moving direction of thenozzles when a developing solution is ejected through the developernozzle 4A (4B). Further, a nozzle which has a common ejection port forejecting a developing solution and a rinse liquid (and a surfactant asnecessary) may be used.

Instead of the foregoing mechanism for linearly moving the developernozzle 4A (4B), a mechanism that swings the nozzle arm around a verticalaxis. In this case, the developer nozzle 4A (4B) is moved from theperipheral edge of the wafer W toward the center portion of the wafer Walong a circular arc to supply a developing solution to the wafer W.

In the present invention, the substrate processed in the abovedeveloping apparatus is not limited to a wafer W, and may be, forexample, an LCD substrate or a reticle substrate for a photomask. Notethat the above configuration of the developer nozzle 4A (4B) can beapplied to a coating liquid nozzle for coating a resist onto asubstrate.

There will now be described an exemplary configuration of acoating-and-developing apparatus incorporating the above developingapparatus with reference to FIGS. 15 and 16. In these figures, referencenumeral B1 denotes a carrier mounting section for transferring carriersC to and from the coating-and-developing apparatus, each carrier C beingairtight and containing a plurality of wafers W (for example, 13 wafersW). The carrier mounting section B1 includes: a carrier station 90having a mount stage 90 a on which a plurality of carriers C can bemounted; shutters 91 provided in the wall surface in front of thecarrier station 90; and a transfer device A1 for removing wafers W fromthe carriers C through the shutters 91.

A processing section B2 enclosed in an enclosure 92 is connected to thecarrier mounting section B1. Unit towers U1, U2, and U3 are disposedwithin the processing section B2 such that the carrier mounting sectionB1 and the unit towers U1, U2, and U3 are adjacent each other in thatorder. Each unit tower is composed of pluralities of heating units andcooling units stacked on one another. Main transfer devices A2 and A3are provided between adjacent unit towers to transfer wafers W betweenprocessing units including coating units and developing units. Each unittower includes a transfer unit. The wafers W can be transferred from theunit tower U1 to the unit tower U3 within the processing section B1through these transfer units. The main conveyer A2 and A3 are installedin the spaces defined by sides of unit towers (U1, U2, U3), sides ofliquid processing unit towers (U4, U5), and partition walls 93. In thefigures, reference numerals 94 and 95 denote temperature/humiditycontrol units each including a temperature control device forcontrolling the temperature of processing liquids used in each unit, atemperature/humidity control duct, etc.

The liquid processing unit towers U4 and U5 each include a storage unit96 for storing chemical solutions, such as coating liquids (resistliquids) and developing solutions, and a plurality of other units (forexample, 5 other units) stacked on one another over the storage unit 96.These units include: coating units COT; developing apparatuses of thepresent invention, that is, developing units DEV; and/or antireflectivefilm forming units BARC. The unit towers U1, U2, and U3 each includepluralities of various units (e.g., 10 units) stacked on one another forpre-processing and post-processing for the liquid processing performedby the liquid processing units U4 and U5. These various units includebaking units, cooling units, etc.

An exposure section B4 is connected to the far side of the unit tower U3of the processing section B2 through an interface section B3 thatincludes a first transfer chamber 97 and a second transfer chamber 98.The interface section B3 further includes: two transfer devices A4 andA5 for transferring wafers W between the processing section B2 and theexposure section B4; a unit tower U6; and a buffer carrier C0.

There will now be described the flow of steps for processing each waferin this system. First, when a carrier C containing wafers W has beenbrought into the coating-and-developing apparatus and placed on themount stage 90, the shutter 91 and the cover of the carrier C are openedand a wafer W is removed from the carrier C by the transfer device A1.Then, the wafer W is transferred to the main transfer device A2 throughthe transfer unit provided in the unit tower U1, and subjected to apretreatment process for a coating process in one of the unit towers U1to U3 (for example, subjected to an antireflective film forming processand a cooling process). After that, the wafer W is coated with a resistliquid in a coating unit COT. Then, after being heated in a baking unitprovided in one of the unit towers U1 to U3, the wafer W is cooled andtransferred to the interface section B3 through the transfer unit of theunit tower U3. The wafer W is then transferred to the exposure sectionB4 through the transfer device A4, the unit tower U6, and the transferdevice A5 in the interface section B3. Then, after being exposed in theexposure section B3, the wafer W is transferred back to the maintransfer device A2 through the same passage in reverse and thendeveloped in the developing unit DEV, thereby formation of a resist maskis completed. After that, the wafer W is returned to the originalcarrier C on the mounting stage 90.

1: A developing method comprising: holding a substrate in a horizontal attitude on a substrate holding unit, the substrate having an exposed resist thereon; moving a developer nozzle having an ejection port having a shape of an elongated slit whose length measured in a longitudinal direction thereof is smaller than a radius of the substrate, while a moving direction of the developer nozzle being oriented parallel to the longitudinal direction of the ejection port, and while ejecting a developing solution in a form of a strip from the ejection port, thereby spirally supplying the developing solution onto a surface of the substrate while allowing the developing solution to flow radially outwardly; and stopping supplying the developing solution through the developer nozzle and supplying a rinse liquid to the surface of the substrate through a rinse liquid nozzle. 2: The developing method according to claim 1, wherein the ejection port of the developer nozzle has a width in a range of 0.1 mm to 1 mm and a length in a range of 8 mm to 15 mm. 3: The developing method according to claim 1, wherein the temperature of the developing solution is controlled according to a type of the resist, to be developed, on the substrate or a specific geometrical characteristic of a pattern of the resist. 4: The developing method according to claim 1, further comprising: selecting one of a plurality of developer nozzles, which have been set to eject developing solutions at different temperatures, based on a type of the resist to be developed on the substrate or a specific geometrical characteristic of a pattern of the resist. 5: The developing method according to claim 4, further comprising: while one developer nozzle is selected, adjusting the temperature of a developing solution for another developer nozzle. 6: The developing method according to claim 1, wherein the temperature and concentration of the developing solution are controlled according to a type of the resist, to be developed, on the substrate or a specific geometrical characteristic of a pattern of the resist. 7: The developing method according to claim 6, further comprising: while one developer nozzle is selected, adjusting the temperature and concentration of a developing solution for another developer nozzle. 8: The developing method according to claim 1, further comprising: moving the rinse liquid nozzle to a position near the developer nozzle before the developer nozzle stops ejecting the developing solution. 9: The developing method according to claim 1, wherein the developing solution supplying includes moving the developer nozzle from the periphery of the substrate toward the center portion of the substrate a plurality of times while ejecting a developing solution through the developer nozzle. 10: The developing method according to claim 1, wherein the developing solution supplying includes supplying the developing solution to the center portion for a predetermined period of time, after moving the developing solution nozzle from the periphery of the substrate toward the center portion of the substrate. 11: The developing method according to claim 1, further comprising: supplying a surface treatment liquid to the surface of the substrate to enhance wettability of the surface of the substrate, before supplying the developing solution. 12: The developing method according to claim 1, further comprising: supplying a rinse liquid to the surface of the substrate after supplying the developing solution; and supplying a surfactant to the surface of the substrate, after supplying the rinse liquid. 13: The developing method according to claim 1, wherein movement of the developer nozzle from the outer portion of the substrate toward the center portion of the substrate is stopped when an end, on a side of the center portion of the substrate, of the ejection port of the developer nozzle has reached a position corresponding to the rotational axis of the substrate. 